Bore cleaner

ABSTRACT

A composition, useful for removal of residues from gun barrels deposited during firing, consisting essentially of from 5 to 15 percent by volume of N,N-dimethyl formamide, from 40 to 50 percent by volume of ethylene glycol, and remainder substantially distilled water. Preferably, up to 0.1 percent by volume of a nonionic wetting agent, and a trace of a water soluble dye, are included.

United States Patent References Cited UNITED STATES PATENTS 7/ 1929 Haff 9/1958 Bloch et a1...

4/1965 Morison r. 6/1967 Rosenfeld FOREIGN PATENTS 5/1923 Great Britain Primary Examiner-Leon D. Rosdol Assistant Examiner-William E. Schulz Attrneyler0me P. Bloom ABSTRACT: A composition, useful for removal of residues from gun barrels deposited during firing, consisting essentially of from to percent by volume of N,N-dimethyl forma' mide, from 40 to percent by volume of ethylene glycol, and remainder substantially distilled water. Preferably, up to 01 percent by volume of a nonionic wetting agent, and a trace of a water soluble dye, are included.

BORE CLEANER BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a liquid cleaner for gun bores which removes, in a single application, residues deposited as a result of firing; including the decomposition products of potassium chlorate primers, and of phthalate type deterrents used in ball powders. The composition is effective in removing such deposits, even in many cases without the necessity of using brass brushes, or other abrasive type cleaning devices, and does not require rinsing of the gun barrel after application of the cleaner.

2. Description of the Prior Art The recent trend, to use of ball powder, has resulted in serious problems of fouling of gun bores; apparently because of the use of dibutyl phthalate and diphenyl phthalate applied to the powder as coatings to act as a deterrent or stabilizer. The use of potassium chlorate priming also results in deposition of residues which are hygroscopic and cause rust to form in a gun bore if not removed promptly.

The problems caused by bore fouling are summarized in American Reloaders Association Bulletin, Vol. 65, Jan. 1969, page 8, as follows:

I strongly suspect the heavy deterrent coatings of the phthalate types used on some of the ball powders such as (particularly) H-380 are almost immune to common solvents, but could be cut by the right solvents. Hoppes 09 hardly touches these deposits. It takes prolonged cleaning and scrubbing with brass brushes before you finally get the accuracy back (if you do) and you can nearly enlarge the bore to the next caliber in the effort of the process. The American Rifleman recently reported that in some cases of accuracy loss from powder fouling, original accuracy was never regained, even after the most energetic cleaning, once the loss had occurred. Using BL-CZ, Ive gotten my good .222 so messy that the black goop was not removable by consecutive cleanings with paint thinner, Hoppes, trichlor and lacquer thinner, plus beaucoup brushing with a brass brush in the meantime. Even after the rags came out clean, Ive then used Torn Rice's solvent and again produced coal black swabs from the supposedly clean bore. 1 sured like to see this problem tackled on the chemical level as it would be a great boon to shooters. And its not metal fouling-as discussed in a recent ARAB-though it may contribute to it. I think the very slow extruded powders, such as Normas 205 are also very heavily coated.

It is apparent from the above quotation that prior art gun bore cleaners are mixtures of organic solvents of various types (predominantly petroleum distillates) which are flammable and have relatively low flash points. Hence, in addition to being ineffective in removing residues from gun bores, they are inherently dangerous to use, unless special precautions are observed. Moreover, the odor of such solvents is objectionable to many persons.

SUMMARY It is a principal object of the present invention to provide a liquid cleaning composition for gun bores which is effective in removing residues substantially, completely in a single application without undue effort, which is nonirritating to the user, which is nonflammable and substantially odorless, and which does not require rinsing of the gun bore after cleaning.

The above object and advantages are achieved in the present invention by a cleaning composition consisting essentially of from to percent by volume of dimethyl formamide, from 40 to 50 percent by volume of ethylene glycol, and balance substantially water.

In the preferred practice of the invention the composition contains 10 percent dimethyl formarnide, 45 percent ethylene glycol, 0.05 percent of an aliphatic oxyethylated alcohol, a trace of a water-soluble dye, and balance distilled water, all percentages being by volume.

In the above preferred composition the aliphatic oxyethylated alcohol is used as a wetting agent, and the dye may be DuPont Blue A" which is added for ready identification of the composition.

While the effectiveness of N,N-dimethyl formamide (hereinafter referred to as DMF for convenience) as an organic solvent is well known, its use has been quite restricted because it is highly irritating to the skin, eyes and mucous membranes. Paint stripping compositions containing from 50 to percent by volume of DMF are disclosed in U.S. Pats. Nos. 3,324,039 and 3,179,609. The use of DMF as a solvent for nylon and ORLON (Registered Trademark) has also been disclosed.

It is apparent that compositions of the above type containing large amounts of DMF could not be used without special precautions to protect the skin and eyes of the user under conditions where handling and close contact with the composition cannot be avoided. Moreover, the high percentage of other volatile organic compounds renders such prior art compositions highly flammable and would preclude their use under any but carefully controlled conditions.

For these reasons there has never been any suggestion in the prior art, to the best of applicants knowledge, that compositions containing DMF would be effective as a gun bore cleaner.

Surprisingly, it has now been discovered that a composition according to the invention containing as little as 5 percent DMF by volume is highly effective in removing residues deposited in gun barrels resulting not only from the use of potassium chlorate primers but also of phthalate type deterrents used in ball powders. Moreover, it has further been discovered that as much as 15 percent by volume of DMF in such a composition is not irritating to the skin and eyes of the user and can be used without special precautions under a wide variety of conditions. DESCRIPTION OF THE PREFERRED EMBODIMENTS In the composition of the present invention N,N-dimethyl formamide is present in amounts from 5 to 15 percent by volume. Less than 5 percent results in ineffective removal of residues in a gun bore deposited by firing of the gun. More than 15 percent by volume is undesirable, since above this percentage the irritating effect becomes noticeable.

From 40 to 50 percent by volume of ethylene glycol is present in the composition The ethylene glycol lowers the freezing point of the composition, reduces the irritating effect of DMF and stabilizes the composition, thereby preventing separation of the components at low temperatures.

The balance of composition of the invention is substantially water. The water should be low in hardness or treated with a water softener in order to avoid deposits of calcium salts within the gun bore after the composition dries. Preferably distilled water is used.

In the preferred composition up to 0.1 percent by volume of a nonionic wetting agent is added to the composition to accelerate penetration of the deposited residues by the liquid cleaning composition. Preferably 0.05 percent by volume of an aliphatic oxyethylated alcohol, or an alkaryl oxyethylated alcohol, is added as a wetting agent, e.g., surfactants sold under the registered trademarks Igepal CA620" and Hallco CPH-30 which are shown by McCutcheon in the 1963 annual of Detergents and Emulsifiers on page 73 and 69 to be Octylphenoxy poly(ethylene oxy) ethanol and propylene glycol mono laurate respectively.

In the preferred composition a trace of a water-soluble dye, such as DuPont Blue A is added so that the composition can be readily identified and distinguished even if the label should be lost from the container.

In the present composition a retardant, i.e., a material which delays evaporation, is not necessary, since the composition immediately attacks and dissolves deposits within a gun bore.

EXAMPLE I A cleaning composition according to the invention was prepared with the following formulation: percent by volume dimethyl formamide, 45 percent by volume ethylene glycol, 44.95 percent by volume distilled water, 0.05 percent by volume aliphatic oxyethylated alcohol, trace DuPont Blue A dye.

The DMF may be added directly to the water since it is miscible therewith in the proportions specified in the present invention, although the order of mixing of the components is immaterial. The resulting composition is a stable single phase liquid which shows no separation of components or freezing down to 20F. The composition is nonflammable and virtually odorless, and has substantially constant viscosity at normally encountered temperatures.

A number of standard charges of ball powder were fired in a gun, followed by charges reduced 25 percent in order to accelerate fouling. Firing was continued to the point where group dispersion at the target increased several times normal, and an occasional bullet keyholed. The gun bore was then treated with the composition of Example I and a cloth swab run through the bore to remove the dissolved deposit. It was found that all residue was removed in a single cleaning, including that deposited by the use of potassium chlorate priming and dibutyl phthalate and diphenyl phthalate deterrent.

EXAMPLE II A composition particularly effective in removing potassium chlorate priming has the following formulation: 5 percent by volume dimethyl formamide, 45 percent by volume ethylene glycol, 49.9 percent by volume distilled water, and 0.1 percent by volume lgepal CA-620."

This composition is nonflammable, odorless, stable and exhibits no separation of phases or freezing down to about 5 F.

EXAMPLE [[1 A composition having optimum cleaning effectiveness for gun bores heavily fouled by firing ball powder charges has the following formulation: percent by volume dimethyl formamide, 40 percent by volume ethylene glycol, 44.95 percent by volume distilled water and 0.05 percent by volume of a nonionic wetting agent.

This liquid composition is nonflammable, has very slight odor, and is stable down to about 15 F.

The composition of the present invention has a viscosity somewhat greater than that of ordinary water, as a result of the presence of ethylene glycol, and hence can be used quite conveniently. The stability and low freezing point of the composition also render it suitable for use even under the most extreme outdoor weather conditions.

Modifications may be made in the invention without depart- .ing from the spirit thereof, and it will be understood that all matter described herein is to be interpreted as illustrative and not as a limitation.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A composition for removal of residues from gun bores deposited as a result of firing, consisting essentially of from 5 to 15 percent by volume of N,N-dimethyl formamide, from 40 to 50 percent by volume of ethylene glycol, and remainder substantially water.

2. The composition of claim 1, including up to 0.1 percent by volume of a nonionic wetting agent.

3. The composition of claim 1, including a trace of a watersoluble dye.

4. The composition of claim 1, wherein said N ,N-dimethyl formamide is present in an amount of about 10 percent by volume.

5. The composition of claim 1, wherein said ethylene glycol is present in an amount of about 45 percent by volume.

. A stable, single-phase liquid cleaning composition consisting essentially of about 10 percent N,N-dimethyl formamide, about 45 percent ethylene glycol, about 0.05 percent aliphatic oxyethylated alcohol, a trace of a water-soluble dye, and balance substantially distilled water, all percentages being by volume, said composition being nonflammable and substantially odorless, and having a freezing point below about 20 F. 

2. The composition of claim 1, including up to 0.1 percent by volume of a nonionic wetting agent.
 3. The composition of claim 1, including a trace of a water-soluble dye.
 4. The composition of claim 1, wherein said N,N-dimethyl formamide is present in an amount of about 10 percent by volume.
 5. The composition of claim 1, wherein said ethylene glycol is present in an amount of about 45 percent by volume.
 6. A stable, single-phase liquid cleaning composition consisting essentially of about 10 percent N,N-dimethyl formamide, about 45 percent ethylene glycol, about 0.05 percent aliphatic oxyethylated alcohol, a trace of a water-soluble dye, and balance substantially distilled water, all percentages being by volume, said composition being nonflammable and substantially odorless, and having a freezing point below about -20* F. 